class mammalia subclass prototheria †order triconodonta
TRANSCRIPT
Class MammaliaSubclass Prototheria
‡ Order TriconodontaMorganucodontidaeAmphilestidaeTriconodontidae
‡ Order DocodontaOrder Monotremata
‡ Subclass AllotheriaOrder HaramiyoideaOrder Multituberculata
Subclass Theria‡ Infraclass Trituberculata
Order SymmetrodontaKuehnoetheriidae
Order EupantotheriaDryolestidae
Infraclass MetatheriaInfraclass Eutheria
(After Carroll 1988)
‡“Class” MammaliformesOrder Morganucodontia
MorganucodontidaeOrder DocodontaOrder Haramiyoidea
Class MammaliaSubclass Prototheria
Order PlatypodaOrder Tachyglossa
Subclass Theriiformes‡ Infraclass Allotheria
Order Multituberculata‡ Infraclass Triconodontia
Infraclass Holotheria‡ Order Symmetrodontia‡ Order Eupantotheria
Order MetatheriaOrder Eutheria
(After McKenna & Bell 1997)
PROTOTHERIA -- Order MonotremataFamily Ornithorhynchidae (fossil history)
ObdurodonMiocene, Australia
OrnithorhynchusRecent
Deciduous teeth
SteropodonCretaceous, Australia
MonotrematumPaleocene, South America Kollikodon
Cretaceous, Australia
PROTOTHERIA -- Order MonotremataFamily Tachyglossidae (echidnas)
TachyglossusShort-beaked echidna
(Australia, Tasmania, New Guinea)
PROTOTHERIA -- Order MonotremataFamily Tachyglossidae (echidnas)
ZaglossusLong-beaked echidna
(New Guinea)
PROTOTHERIAN - THERIAN CONTRASTS
PROTOTHERIANS THERIANS(monotremes) (marsupials &
placentals)
TeethDeciduous teeth only Permanent dentition
multi-cusped molars tribosphenic molars
Skeleton Therapsid features:
skull with “extra” bones fusion of skull bonescervical ribs cervical ribs lost
“reptilian” shoulder girdle “mammalian” shoulder sprawling limb posture upright limb posture
Reproduction“reptilian” cloacal opening separate urogenital &
anal openingsoviparous viviparousmammary glands not well-developed teats
forming teats